Matrix Factorization methods

The last.fm story continued…

From previous projects, we:

  • Got listen count data from last.fm
  • Filtered out the bad rows (?????)
  • Derived a 0 to 5 score based on the listen count
  • Performed top-N suggestions using UBCF (User Based Collaborative Filtering)
  • Performed top-N suggestions using IBCF (Item Based Collaborative Filtering)

Now, we:

  • Query google for “top [music_genre] bands” for 5 specific genres
  • Set user 1 to rate (only) google’s top 5 bands for that genre a 5/5
  • Use recommenderlab’s “SVD” strategy to suggest bands when K=200, 100, 50 and 10
  • Analyze the differences in K values, see if our suggestions match any of google’s top 18

SVD: google “top classic rock bands”


If USER_1 likes the following artists:

userID artistID artist listen_count
1 227 The Beatles 5
1 1412 Led Zeppelin 5
1 163 Pink Floyd 5
1 706 AC/DC 5
1 1249 Guns N’’ Roses 5

Then we suggest:

K User Rec_1 Rec_2 Rec_3 Rec_4 Rec_5 Rec_6 Rec_7
500 1 Johann Sebastian Bach Johannes Brahms Gramofocas The Who Nightwish American Hi-Fi Scorpions
200 1 Nightwish The Who Slipknot Gramofocas Queen Johann Sebastian Bach Bob Marley
100 1 Slipknot Nightwish Queen Avenged Sevenfold Pearl Jam Iron Maiden The Who
50 1 Metallica Iron Maiden Nirvana Queen Scorpions RBD Black Sabbath
10 1 Coldplay Oasis Muse The Killers Radiohead Depeche Mode The Cure

SVD: google “top christian contemporary bands”


If USER_1 likes the following artists:

userID artistID artist listen_count
1 14042 MercyMe 5
1 7756 Casting Crowns 5
1 17875 Newsboys 5
1 7754 Third Day 5
1 371 Skillet 5

Then we suggest:

K User Rec_1 Rec_2 Rec_3 Rec_4 Rec_5 Rec_6 Rec_7
500 1 A Day to Remember Low Shoulder Darin Switchfoot Cut Copy The Fray Marilyn Manson
200 1 Adam Lambert Marilyn Manson Rammstein The Ting Tings Björk Madonna The Fray
100 1 Katy Perry Madonna Marilyn Manson Eminem Rammstein Beyoncé Adam Lambert
50 1 Marilyn Manson Three Days Grace Stone Sour Trivium Green Day Good Charlotte Epica
10 1 The Beatles Nirvana Muse Red Hot Chili Peppers Queen AC/DC System of a Down

SVD: google “top old school rap bands”


If USER_1 likes the following artists:

userID artistID artist listen_count
1 276 Gang Starr 5
1 9821 Run-D.M.C. 5
1 2698 Public Enemy 5
1 605 Beastie Boys 5
1 619 A Tribe Called Quest 5

Then we suggest:

K User Rec_1 Rec_2 Rec_3 Rec_4 Rec_5 Rec_6 Rec_7
500 1 Big Punisher 2Pac Mobb Deep OutKast Cannibal Ox Common LL Cool J
200 1 2Pac Wu-Tang Clan The Killers Big Punisher Method Man Nirvana Cannibal Ox
100 1 The Killers Nirvana Kanye West Eminem Nine Inch Nails Wu-Tang Clan Lupe Fiasco
50 1 Eminem The Smiths Elliott Smith The Killers Kanye West Lupe Fiasco Rise Against
10 1 The Beatles Nirvana Muse Red Hot Chili Peppers Queen AC/DC Led Zeppelin

SVD: google “top folk bands”


If USER_1 likes the following artists:

userID artistID artist listen_count
1 227 The Beatles 5
1 211 The Decemberists 5
1 1633 Fleet Foxes 5
1 2265 Simon & Garfunkel 5
1 429 The Smiths 5

Then we suggest:

K User Rec_1 Rec_2 Rec_3 Rec_4 Rec_5 Rec_6 Rec_7
500 1 Blondie Pavement Metric Modest Mouse Ride Antony and the Johnsons Grandaddy
200 1 Modest Mouse The Clash Blondie Pixies Pavement Pulp Bruce Springsteen
100 1 The Clash Pixies Modest Mouse Bruce Springsteen The White Stripes Simple Minds Pet Shop Boys
50 1 Muse The Killers Arctic Monkeys RBD The White Stripes Anahí Kaiser Chiefs
10 1 Coldplay Oasis Muse The Killers Radiohead Depeche Mode Red Hot Chili Peppers

SVD: google “top funk bands”


If USER_1 likes the following artists:

userID artistID artist listen_count
1 3776 Funkadelic 5
1 3778 Sly & The Family Stone 5
1 8998 Kool & The Gang 5
1 987 Earth, Wind & Fire 5
1 8993 Cameo 5

Then we suggest:

K User Rec_1 Rec_2 Rec_3 Rec_4 Rec_5 Rec_6 Rec_7
500 1 Madlib Isaac Hayes Onra Gil Scott-Heron Zoé Juanes Garbage
200 1 Garbage The Rolling Stones t.A.T.u. Ellie Goulding Zoé Kasabian Armin van Buuren
100 1 Florence + the Machine Maroon 5 Sufjan Stevens Ellie Goulding Out of Ether Michael Cardenas Green Day
50 1 The Beatles Aphex Twin New Order Green Day Out of Ether David Bowie Boards of Canada
10 1 The Beatles Nirvana Muse Red Hot Chili Peppers Queen AC/DC Led Zeppelin

Conclusions